Operating systems are designed and typically optimized based on specific applications and user desired performance. It is often desirable to have applications of one type of operating system available to another operating system.
General-purpose computer operating systems such as Linux™ and Windows™ have an extensive set of features such as file systems, device drivers, applications, libraries, etc. Such operating systems allow concurrent execution of multiple programs, and attempt to optimize the response time (also referred to as latency time), and CPU usage, or load, associated to the servicing of the concurrently executing programs. Unfortunately, however, such operating systems are not generally suitable for embedded real-time applications, such as for mobile computing devices. Under certain circumstances it would be desirable for a mobile computing device to have the performance associated with a mobile-specific embedded operating system and features of a general-purpose operating system.
Linux, for example, is a well known general purpose desktop operating system with many desirable features for modern devices including modern operating systems features, numerous development tools, networking, etc. However, Linux was not designed to be an embedded or real time operating system. Many modern devices, such as, without limitation, set top boxes, mobile phones and car navigation systems require not only the features of a general purpose operating system such as Linux, but also the features of an embedded or real time operating system, including real time performance.
Given that Linux-based operating systems offer some benefits but that other types of operating systems offer other benefits, particularly in the context of certain types of devices such as mobile devices, it would be desirable if somehow multiple operating systems could be implemented on a single device so that the benefits of each different type of operating system could be achieved in relation to that device. Running multiple operating systems on a single device has been accomplished through virtualization techniques, such as (for example) found in VMware™, VirtualBox™, QEMU™, etc. However, when using virtualization a complete computer is emulated and one or more software stacks are operated in the emulated computing device. Emulation is wrought with high overhead costs, and consequently conventional virtualization techniques are often impractical, especially again in the context of certain types of devices such as mobile devices.
In view of the foregoing, there is a need for a new type of operating system implementation by which the benefits of multiple distinct operating systems can be achieved with less overhead costs than would otherwise be the case using conventional virtualization techniques.